DOCK8 deficiency is a combined immunodeficiency disease that is characterized by severe problems with recurrent, persistent, and progressive infections, especially of the skin. This is a major contributing factor to the high morbidity and mortality seen in this disease. However, another key feature of DOCK8 deficiency is the allergic disease: patients typically have severe eczematous dermatitis, asthma, and life-threatening food allergies, often accompanied by high levels of serum IgE and eosinophilia. Most studies to date have focused on the infectious but not the allergic complications of this disease. In FY2017, we contributed to a report that investigated the cellular mechanisms involving abnormalities in T helper subsets and how they contribute to the predisposition to allergies, viral infections, and fungal infections found in a large group of DOCK8-deficient patients. In addition, we contributed to a different report on seven DOCK8-deficient patients who had undergone hematopoietic stem cell transplantation at the NIH Clinical Center using haploidentical donors. Their overall positive outcomes support the use of this alternative curative approach in patients without any matched unrelated or related donors, thereby expanding their treatment options.